If you run Apache Cassandra, you can monitor it with the help of Nagios and JMX. Apache Cassandra has come to “change the world”, I was told at the Cassandra Summit, back in September. It has certainly made a splash, like a gorilla in a bathtub. Problems can come up with new deployments of technology. It can be a challenge to stabilize something that is brand new, and changing so fast. Nagios monitoring can greatly assist in the management and running of Cassandra rings. First of all, your team will gain a better understanding of your infrastructure from the process of implementing Nagios monitoring and the order which will come from cataloging the Cassandra services that you need to monitor. Secondly, once putting the various checks in place, your team will benefit from understanding when exceptions to the norm occur, and this will give you a better understanding of the status of your application health. Third, since you will be able to rely on Nagios to alert you when there is a problem, your team will be able to spend more time on improving your infrastructure, and less on watching instrumentation.

The best tools to use for creating useful Cassandra plugins for Nagios are:

  1. check_jmx – a tool found on the Nagios Exchange which can be used to check JMX integer value attributes. This is an easy tool to get working, but is limited by its simplicity. It can only check one integer attribute. Though one could wrap this check into another script, to check more than one attribute, or do anything more sophisticated. Another limitation of this check is that check_jmx does not support JMX authentication.
  2. cmdline-jmxclient.jar – this tool is also very easy to use but does not come packaged as a Nagios plugin so you must wrap it in your own plugin code, which you write. The advantage for this tool is that you can grab all the attributes at once, which makes it much easier to write checks that must grab more than one attribute to evaluate the check state. Also, this plugin works with JMX authentication, so if you must use JMX authentication, then you must use this method to write your Cassandra JMX plugins.

Rex Consulting can restore order to your environment. We have experience setting up Nagios on Cassandra and can plan and implement your Nagios monitoring system. We are also highly skilled in the development of custom monitoring checks to fit your special needs. Contact Rex Consulting today to begin a plan for your monitoring system.

© Copyright 2020 Rex Consulting, Inc. – All rights reserved